Computers and Networks (Unit 4)
Add Definitions from Unit 4 Computer Systems and Networks
Requirements
Work through College Board Unit 4… blog, add definitions, and pictures. Be creative, for instance make a story of Computing and Networks that is related to your PBL experiences this year.
The Internet:
- A computing device is a physical artifact that can run a program. Some examples include computers, tablets, servers, routers, and smart sensors
- A computing system is a group of computing devices and programs working together for a common purpose.
- A computer network is a group of interconnected computing devices capable of sending or receiving data.
- The Internet is a computer network consisting of interconnected networks that use standardized, open (nonproprietary) communication protocols.
Fault Tolerance:
- The Internet has been engineered to be faulttolerant, with abstractions for routing and transmitting data
- Redundancy is the inclusion of extra components that can be used to mitigate failure of a system if other components fail.
- When a system can support failures and still continue to function, it is called fault-tolerant.
- This is important because elements of complex systems fail at unexpected times, often in groups, and fault tolerance allows users to continue to use the network.
- The redundancy of routing options between two points increases the reliability of the Internet and helps it scale to more devices and more people.
Parallel/Distributed Computing
- Sequential computing is a computational model in which operations are performed in order one at a time.
- Parallel computing is a computational model where the program is broken into multiple smaller sequential computing operations, some of which are performed simultaneously.
- When increasing the use of parallel computing in a solution, the efficiency of the solution is still limited by the sequential portion. This means that at some point, adding parallel portions will no longer meaningfully increase efficiency.
How a Computer Works
As we have learned, a computer needs aa program to do something smart. The sequence of a program initiates a series of actions with the computers Central Processing Unit (CPU). This component is essentially a binary machine focussing on program instructions provided. The CPU retrieives and stores the data it acts upon in Random Access Memory (RAM). Between the CPU, RAM, and Storage Devices a computer can work with many programs and large amounts of data.
List specification of your Computer, or Computers if working as Pair/Trio
- Processor GHz: 3.00
- Memory in GB: 8.00
- Storage in GB: 236
- OS: Windows 11 Home
Define or describe usage of Computer using Computer Programs. Pictures are preferred over a lot of text. Use your experience.
- Input devices: hardware devices used to enter data or commands into a computer, like a keyboard, mouse, or scanner
- Output devices: hardware, used to display or output data from a computer, like a monitor, printer, or speaker
- Program File: contains executable instructions or code that can be run by a computer to perform specific tasks
- Program Code: instructions written in a programming language that can be compiled or interpreted by a computer
- Processes: instances of programs running on a computer that are managed by the operating system
- Ports: physical or virtual communication channels through which data is transferred between a computer and other devices
- Data File: contains data, such as text, images, or videos, which can be accessed and modified by programs
- Inspect Running Code: examine the code of a program that is currently running in memory, like using debugging
- Inspect Variables: examine the values of variables used by a program during its execution
The Internet
Watch/review College Board Daily Video for 4.1.1
- Essential Knowledge
- A computing device is a physical artifact that can run a program. Some examples include computers, tablets, servers, routers, and smart sensors.
- A computing system is a group of computing devices and programs working together for a common purpose.
- A computer network is a group of interconnected computing devices capable of sending or receiving data.
- A computer network is a type of computing system.
- A path between two computing devices on a computer network (a sender and a receiver) is a sequence of directly connected computing devices that begins at the sender and ends at the receiver.
- Routing is the process of finding a path from sender to receiver.
- The bandwidth of a computer network is the maximum amount of data that can be sent in a fixed amount of time.
- Bandwidth is usually measured in bits per second
- Complete Vocabulary Matching Activity. Incorporate this into your learnings from year. To analyze measure path and latency use
traceroute
andping
commands from Linux Terminal.- Path: where a file is located, within folders and subfolders
- Route: path that something (packet) travels over a network
- Computer System: system within the device (OS) like windows
- Computer Device: physical computing object, like a computer
- Bandwidth: how much data can be transferred across a path
- Computer Network: web of interconnected computers
Watch/review College Board Daily Video 4.1.2
-
Complete True of False Questions
- Essential Knowledge
- The internet is a computer network consisting of interconnected networks that use standardized, open (nonproprierary) communication protocols.
- Access to the internet depends on the ability to connect a computing device to an internet connected device.
- A protocol is an agreed-upon set of rules that specify the behavior of a system.
- The protocols used in the internet are open, which allows users to easily connect additional computing devices to the internet.
- Routing on the internet is usually dynamic; it is not specified in advance
- The scalability of a system is the capacity for the system to change in size and scale to meet new demands.
- The internet was designed to be scalable
- Information is passed through the internet as a data stream. Data streams contain chunks of data, which are encapsulated in packets.
- Packets contain a chunk of data and metadata used for routing the packet between the origin and the destination on the internet, as well as for data reassembly.
- Packets may arrive at the destination in order, out of order, or not at all
- IP, TCP and UDP are common protocols used on the internet.
- The world wide web is a system of linked pages, programs, and files.
- HTTP is a protocol used by the world wide web
- The world wide web uses the internet
- Go over AP videos, vocabulary, and essential knowledge. Draw a diagram showing the internet and its many levels. A preferred diagram would using your knowledge of frontend, backend, deployment, etc. Picture would highligh vocabulary by illustration. The below illustration have some ideas
- Often we draw pictures of machines communicating over the Internet with arrows. However, the real communication goes through protocol layers and the machine and then is trasported of the network. For College Board and future Computer Knowledge you should become familiar with the following …
User Machine <---> Frontend Server <---> Backend Server
+-----------+ +-----------+ +-----------+
| Browser | | GH Page | | Flask |
+-----------+ ^ +-----------+ ^ +-----------+
| HTTP | | | HTTP | | | HTTP |
+-----------+ | +-----------+ | +-----------+
| TCP | | | TCP | | | TCP |
+-----------+ | +-----------+ | +-----------+
| IP | V | IP | V | IP |
+-----------+ +-----------+ +-----------+
| Network | <---> | Network | <---> | Network |
+-----------+ +-----------+ +-----------+
The “http” layer is an application layer protocol in the TCP/IP stack, used for communication between web browsers and web servers. It is the protocol used for transmitting data over the World Wide Web.
The “transport” layer (TCP) is responsible for providing reliable data transfer between applications running on different hosts. The TCP protocol segments the data into smaller chunks called “segments”. Each segment contains a sequence number that identifies its position in the original stream of data, as well as other control information such as source and destination port numbers, and checksums for error detection.
The “ip” layer is responsible for packetizing data received from the TCP layer of the protocol stack, and then encapsulating the data into IP packets. The IP packets are then sent to the lower layers of the protocol stack for transmission over the network.
The “network” layer is responsible for routing data packets between networks using the Internet Protocol (IP). This layer handles tasks such as packet addressing and routing, fragmentation and reassembly, and network congestion control.
Fault Tolerance
Watch both Daily videos for 4.2
- Complete the network activity, summarize your understanding of fault tolerance.
- fault tolerance is creating several connections or failsafes implemented in the case of machinery breaking down
Parallel and Distributed Computing
Review previous lecture on Parallel Computing and watch Daily vidoe 4.3. Think of ways to make something in you team project to utilize Cores more effectively. Here are some thoughts to add to your story of Computers and Networks…
-
What is naturally Distributed in Frontend/Backend archeticture?
Tasks are distributed so that more machines are doing the same total work, but less each, to achieve a result quickly and efficiently. -
Analyze this command in Docker:
ENV GUNICORN_CMD_ARGS="--workers=1 --bind=0.0.0.0:8086"
. Determine if there is options are options in this command for parallel computing within the server that runs python/gunicorn. Here is an article You can increase workers from 1 to 2 to allow two machines to do the work at the same time(parallel computing)
Last week we discussed parallel computing on local machine. There are many options. Here is something to get parallel computing work with a tool called Ray.
- Review this article… Can you get parallel code on images to work more effectively? I have not tried Ray.
- Code example from ChatGPT using squares. This might be more interesting if nums we generated to be a lot bigger.
import ray
# define a simple function that takes a number and returns its square
def square(x):
return x * x
# initialize Ray
ray.init()
# create a remote function that squares a list of numbers in parallel
@ray.remote
def square_list(nums):
return [square(num) for num in nums]
# define a list of numbers to square
nums = [1, 2, 3, 4, 5]
# split the list into two parts
split_idx = len(nums) // 2
part1, part2 = nums[:split_idx], nums[split_idx:]
# call the remote function in parallel on the two parts
part1_result = square_list.remote(part1)
part2_result = square_list.remote(part2)
# get the results and combine them
result = ray.get(part1_result) + ray.get(part2_result)
# print the result
print(result)